This invention relates to a liquid crystal cell. More particularly, it relates to a liquid crystal cell wherein the liquid crystal material thereof is confined between opposed plates of the cell by a terpolymeric fluoroelastomer sealant.
Liquid crystal cells used for the production of display devices are well known and have been described in various patents and publications. In general, these cells comprise a pair of opposed plates spaced apart at a predetermined distance and contain a liquid crystal material confined therebetween. The liquid crystal material is confined between the plates by a gasket or sealant material which can be comprised of inorganic or organic material. Liquid crystal cells and examples of materials used as sealants or gaskets in the production thereof are described, for example, in U.S. Pat. No. 3,700,306 (issued Oct. 24, 1972 to J. V. Cartmell et al.); in U.S. Pat. No. 3,871,746 (issued Mar. 18, 1975 to R. Muto et al.; and in U.S. Pat. No. 3,994,568 (issued Nov. 30, 1976 to H. A. King et al.).
The manufacture and operational efficiency of a liquid crystal cell, or a display device prepared therefrom, can be influenced by the nature of the sealant or gasket material employed in the manufacture of the cell. Inorganic materials such as glass and frit material have, for example, been employed as sealant materials for liquid crystal cells. These materials are not readily processable and generally require high temperatures for application of the sealant material and provision of a suitable bond. These temperatures are particularly disadvantageous where the plates are desirably formed from a plastic material such as polyester or the like. The more readily processable organic polymer sealant materials can also present difficulties in the fabrication of a liquid crystal cell. For example, the integrity of the polymeric seal will oftentimes be sacrificed over a period of time by chemical attack or degradation of the sealant material by the liquid crystal material. This in turn can lead to swelling and softening of the sealant material and, in the case of gross failure, can lead to the formation and appearance of bubbles in the liquid crystal cell. The polymeric sealant can also be a source of liquid crystal contamination as a consequence of diffusion of contaminants from the polymeric sealant material into the liquid crystal material confined between the opposing plates of the cell. This can lead to inefficiency in the electrical operation of the cell and premature failure of the cell.